To meet the demand for wireless data traffic having increased since deployment of 4G communication systems, efforts have been made to develop an improved 5G or pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a ‘Beyond 4G Network’ or a ‘Post LTE System’.
The 5G communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, so as to accomplish higher data rates. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), Full Dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G communication systems.
In addition, in 5G communication systems, development for system network improvement is under way based on advanced small cells, cloud Radio Access Networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), reception-end interference cancellation and the like.
In the 5G system, Hybrid FSK and QAM Modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as an advanced access technology have been developed.
Generally, in a multi-user multi-input multi-output (MU-MIMO) and single-user multi-input multi-output (SU-MIMO) system supporting digital beamforming, a mobile station (MS) determines a channel quality index (CQI) and a precoding matrix index (PMI) based on a channel state with a base station (BS) for the sake of efficient communication with the BS and feeds back the determined CQI and PMI to the BS, and the BS schedules a plurality of MSs based on CQIs and PMIs fed back from a plurality of MSs.
Meanwhile, recent attention is being paid to a hybrid beamforming system concurrently supporting analog beamforming and digital beamforming. In the hybrid beamforming system, an effective channel can be different in accordance to a combination of analog beams. Accordingly, a situation can occur in which an MS has to determine a PMI by beam combination and select and transmit an optimal PMI to a BS. This method can increase a feedback overhead, and delay scheduling resource allocation, thereby causing uplink performance deterioration. Accordingly, there is a need to suggest a technique of feedback and scheduling of an MS in the hybrid beamforming system concurrently supporting the analog beamforming and the digital beamforming.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.